When continuous business forms are detached, it is highly desirable to provide some sort of a break between different groups of forms so that the detached forms may be handled separately in subsequent operations, such as mailing, printing, or the like. One simple, but effective, way to accomplish separation of the forms for ready handling in subsequent operations is to offset the forms into groups of forms. This is accomplished in a simple and effective manner in U.S. Pat. No. 5,238,164. However, while the offset stacking of forms in the U.S. Pat. No. 5,238,164 patent is highly successful, it is necessary to temporarily arrest the forms processing each time that a change-over from one offset orientation to another is accomplished. This slows down the processing speed, and the slow down can be significant if there are only a few forms in each group.
According to the present invention, a method and apparatus are provided for offsetting stacks of individual business forms in a continuous manner (that is, without interruption), at least until a stacker (if utilized) associated with the operation is full (rather than between each individual grouping of forms). Thus, the method and apparatus according to the present invention provide for higher volume production than discontinuous techniques, and also provide for varying form sizes. Also the equipment utilized according to the present invention is relatively simple so that it is relatively inexpensive and easy to construct and operate.
According to one aspect of the present invention, a method of producing offset stacks of individual business forms in a stacker from a detaching mechanism is practiced. The method comprises the following steps: (a) Automatically continuously detaching continuous business forms in the detaching mechanism to produce individual forms. (b) Automatically continuously feeding the detached individual forms from the detaching mechanism toward the stacker in a first direction. (c) Continuously acting on the individual forms as they are being continuously fed in the first direction to automatically move the forms in a second direction, substantially perpendicular to the first direction, to offset the individual forms into different groups with at least one form in each group. And (d) continuously automatically feeding the individual groups of forms into the stacker to provide stacks, each stack offset from the different stacks before and after it.
The stacker may be a vertical stacker, and step (d) may be practiced until the stacker is full, having a plurality of different stacks therein, and then steps (a) through (d) are interrupted until the stacker is emptied.
Step (c) may be practiced using first and second sets of a plurality of upper forms-engaging elements mounted above and in association with first and second lower forms conveyance structures, respectively. Step (c) is then practiced by sensing the position of the last form in each group and automatically moving the upper forms engaging sets of elements so that the upper elements are removed from operative association with the first of the lower forms conveyance structures and into operative association with the second lower conveyance structures, or vice versa. In one embodiment according to the invention, the upper forms-engaging elements each comprise a plurality of steel balls each mounted adjacent a solenoid, in which case step (c) is practiced by controlling the solenoids to lift the balls of the first upper elements in sequence. The corresponding balls of the second upper elements are dropped in sequence, or vice versa.
According to another aspect of the present invention, apparatus for producing offset stacks of individual business forms is provided comprising the following elements: (a) A detaching mechanism for automatically detaching continuous business forms to produce individual forms. (b) Means for automatically continuously feeding the detached individual forms from the detaching mechanism in a first direction. (c) Means for continuously acting on the individual forms as they are being continuously fed in the first direction to automatically move the forms in a second direction, substantially perpendicular to the first direction, to offset the individual forms into different groups with at least one form in each group. And (d) a stacker for receiving the individual groups of forms in different stacks, each stack offset from the different stacks before and after it.
The stacker may comprise a vertical stacker for containing a plurality of vertical stacks of forms, and the apparatus may further include a sensor for sensing when the stacker is full, and a controller for controlling operation of the apparatus to arrest operation until the stacker is emptied.
The means (c) may comprise first and second sets of a plurality of upper forms-engaging elements mounted above and in association with first and second lower forms conveying structures, respectively; and a plurality of sensors for sensing the position of the last form in each group and automatically moving the upper forms-engaging sets of elements so that the upper elements are removed from operative association with the first of the lower conveying structures and into operative association with the second lower conveying elements, or vice versa. The upper forms engaging elements may each comprise a plurality of steel balls each mounted adjacent a solenoid. The means (c) may then further comprise a controller for controlling solenoids to lift the balls of the first upper elements in sequence when corresponding balls of the second upper elements are dropped in sequence, or vice versa.
According to another aspect of the present invention, apparatus for handling substantially planar elements (such as paper sheets, business forms and the like) to produce offset stacks of substantially planar elements is provided. The apparatus comprises the following elements: A first set of powered bottom conveying structures for conveying substantially planar elements in a first generally horizontal direction. A second set of powered bottom conveying structures for conveying substantially planar elements in a second generally horizontal direction, and positioned with respect to the first direction so that there is an angle of about 2 degrees between the first and second directions. A first set of upper planar element engaging structures for selectively cooperating with the first set of bottom conveying structures and mounted above the first set of bottom conveying structures for selective movement into and out of operative association with the first set of bottom conveying structures. A second set of upper planar element engaging structures for selectively cooperating with the second set of bottom conveying structures and mounted above the second set of bottom conveying structures and mounted above the second set of bottom conveying structures for selective movement into and out of operative association with the second set of bottom conveying structures. A powered mechanism for automatically moving the first set of engaging structures downwardly into operative association with the first set of bottom conveying structures while the second set of engaging structures is moved upwardly out of operative association with the second set of bottom conveying structures, and vice versa.
The first and second sets of bottom conveying structures may comprise first and second angled endless conveyor belts. The first and second sets of upper engaging structures may comprise first and second linear frames each mounting a plurality of rounded surface magnetic material element (e.g. steel balls). The powered mechanism may comprise a solenoid in association with each of the steel balls and when energized lifting the steel ball associated therewith out of operative engagement with a planar element on a bottom conveyance structure, and when deenergized allowing the ball associated therewith to fall into operative engagement with a planar element on a bottom conveyance structure. The solenoid may include a ball engaging element that is contoured to substantially conform to the rounded surface of the ball.
The apparatus preferably further comprises first and second side rails mounted adjacent the first arid second bottom conveying structures for engaging side edges of substantially planar elements as they are conveyed in the first or second direction, the bottom conveying structures being disposed between the first and second side rails. Each of the side rails may be contoured to allow precise engagement of a substantially planar element edge therewith. Also, powered means may be provided for moving the first or second rails toward or away from each other to accommodate substantially planar elements of different widths.
Alternatively, or additionally, the first and second sets of upper engaging structures may each comprise one or more upper diverter wheels and the bottom main structure that is associated with the upper diverter wheels may comprise conveyor belts or one or more lower diverter wheels. For example, the upper diverter wheels may be mounted in pairs, each pair mounted for rotation about a substantially horizontal axis, and a powered mechanism may comprise a motor (e.g. electric motor) for pivoting a shaft about the axis (parallel to the shaft). The pairs of diverter wheels may be connected so that the motor rotates a main shaft to pivot the first set of upper engaging structures in a first direction, the second set of upper engaging structures is automatically pivoted in a second direction opposite the first direction.
As indicated above, the substantially planar elements typically comprise business forms, in which case the apparatus typically is in combination with a continuous business form detaching mechanism located upstream of the conveyance structures in the first and second directions, and a stacker for individual business forms located downstream of the conveyance structures in the first and second directions. A guide assembly is also typically provided between the detaching mechanism and conveyance structures, and a shingling conveyor between the conveyance structures and the stacker.
Typically, a plurality of sensors are provided for sensing the positions of the planar elements as they move in the first or second directions. Control means are also provided for controlling the conveyance structures and powered mechanism in response to the sensors so as to provide continuous operation of the apparatus so that offset stacks of substantially planar elements are formed without interruption between stacks. The control means may comprise means for energizing the solenoids of the first engaging structures in sequence while de-energizing the corresponding solenoids of the second engaging structures in sequence, or vice versa, to provide a smooth and continuous transition from one offset configuration to another.
It is the primary object of the present invention to provide a method and apparatus for continuously producing offset stacks of individual business forms, or like substantially planar elements, in a simple yet effective manner. This and other objects of the invention will become clear from an inspection of the detailed description of the invention, and from the dependent claims.